Thousands of children were held in thrall by the terrible roars, teeth, eyes and claws of Maurice Sendak’s mystical monsters in Where The Wild Things Are.

Fans will remember that the story follows Max, who runs away from an argument with his mother into the wild rumpus of his imagination – before relinquishing his title as king of the wild things to return home for tea.

Now, one grown-up fan has made an incredible discovery in the Connecticut home of the late author and artist, who died in 2012. 

Lynn Caponera, president of the Maurice Sendak Foundation, was going through the writer’s belongings “to see what could be discarded”, when she chanced across an unseen manuscript titled Presto and Zesto in Limboland

According to Publishers Weekly, which broke the story, the undiscovered script featured fully intact illustrations by the author – despite “gathering dust” for years.

Caponera, who has tended to Sendak’s house for decades, did not recognise the script and so she decided to scan it and send it onto Sendak’s long-time editor, Michael di Capua.

“I read it in disbelief,” says di Capua. “What a miracle to find this buried treasure in the archives. To think something as good as this has been lying around there gathering dust.”

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The manuscript is co-authored by Sendak’s friend and frequent collaborator, Arthur Yorinks. “In all honesty, we just forgot it,” he says of the story, which the two authors worked together on in the early 90s.

He explains that the title of the manuscript is actually inspired by Sendak and Yorinks’ nicknames for one another – forged after Sendak welcomed Yorinks at his home one day: “When he opened the door he said, ‘Presto!’ That became my nickname.” Yorinks, in turn, dubbed Sendak “Zesto.”

“It was a hysterical afternoon of cracking each other up,” Yorinks recalls. “But after a few hours a narrative thread began to coagulate. The story became an homage to our own friendship so we named the characters after ourselves—Presto and Zesto.”

After the manuscript was unearthed last year, di Capua called Yorinks and asked if he would be interested in releasing it as a book.

“He asked, ‘Are you interested?’ I said, ‘Holy mackerel. Are you kidding me?’” Yorinks says.

He only had to make a few small revisions: “The memory of writing it originally flooded back in a wonderful kind of way. We always had a lot of laughs for two really depressed guys,” he tells Publishers Weekly.

Barack and Michelle Obama are among the millions of people who’ve been drawn to Sendak’s imaginative fire in Where The Wild Things Are. The former US president and First Lady gave an enthusiastic rendition of the story, complete with theatrical faces and roars, for an audience of schoolchildren in 2015.

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Sendak’s monsters in the book were inspired by his own relatives who used to visit him in Brooklyn and pinch his cheeks (“All crazy – crazy faces and wild eyes”). During his lifetime, he was flooded with letters from young fans all over the world – but one in particular stood out:

“A little boy sent me a charming card with a little drawing on it. I loved it,” the late, great author once said. “I answer all my children’s letters—sometimes very hastily—but this one I lingered over. I sent him a card and I drew a picture of a Wild Thing on it. I wrote, ‘Dear Jim: I loved your card.’ Then I got a letter back from his mother and she said, ‘Jim loved your card so much he ate it.’ 

“That to me was one of the highest compliments I've ever received. He didn't care that it was an original Maurice Sendak drawing or anything. He saw it, he loved it, he ate it.”

 Presto and Zesto in Limboland will be published in autumn 2018.

Images: Rex Features/ Maurice Sendak